In the mild climate of Florida, you can lightly trim live oak trees as needed any time of year. Clipping a low branch tip, removing a suckering shoot from the trunk and cutting off dead or broken branches are examples of such light trimming tasks. It's best to not trim live oaks when they are just emerging from winter dormancy and their new flush of leaves and twigs appear, according to Edward F. Gilman and Dennis G. Watson of the University of Florida. This occurs during March and early April statewide.
If the live oak tree is young and newly planted, perform more substantial limb cutting and pruning maintenance during the winter months, when the tree is dormant. Likewise, it's best to do any structural limb pruning on larger, older trees in winter. Pruning may also be done in summer, but the wounds often quickly sprout lots of weedy, suckering watersprouts that you must remove weeks later.
The size of the live oak tree dictates what trimming or pruning equipment is needed. Trim small trees with the help of a sturdy, A-frame ladder. Larger trees may require you to use a hydraulic lift or an extension pole. Cut branches or twigs less than 3/4 inch in diameter with sharp hand pruners. Use loppers for those between 3/4 and 1 1/2 inch thick. Alternatively, cut any sturdy branch with a diameter over 1 inch with a hand-held pruning saw.
Tropical storms and hurricanes frequent all parts of Florida. The most likely time for storms runs from June to November, with more frequent storms occurring in August and September. Trim and prune live oak trees before the storm season. Trimming the tree's leafy canopy improves the movement of wind through it, making plants more resilient.